(19)
(11) EP 1 125 745 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
24.07.2002 Bulletin 2002/30

(43) Date of publication A2:
22.08.2001 Bulletin 2001/34

(21) Application number: 01103930.2

(22) Date of filing: 16.02.2001
(51) International Patent Classification (IPC)7: B41J 2/14, B41J 2/05
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 18.02.2000 JP 2000042076
18.02.2000 JP 2000042077
18.02.2000 JP 2000042078
18.02.2000 JP 2000042079
02.05.2000 JP 2000133895

(71) Applicant: CANON KABUSHIKI KAISHA
Tokyo (JP)

(72) Inventors:
  • Imanaka, Yoshiyuki
    Ohta-ku, Tokyo (JP)
  • Takagi, Shinji
    Ohta-ku, Tokyo (JP)
  • Saito, Ichiro
    Ohta-ku, Tokyo (JP)
  • Inui, Toshiharu
    Ohta-ku, Tokyo (JP)
  • Yano, Kentaro
    Ohta-ku, Tokyo (JP)
  • Ikeda, Tetsuhito
    Ohta-ku, Tokyo (JP)
  • Kato, Masao
    Ohta-ku, Tokyo (JP)
  • Takahashi, Katsuhiko
    Ohta-ku, Tokyo (JP)
  • Mochizuki, Muga
    Ohta-ku, Tokyo (JP)
  • Saito, Kenichi
    Ohta-ku, Tokyo (JP)
  • Sato, Tomonori
    Ohta-ku, Tokyo (JP)
  • Kubokawa, Toru
    Ohta-ku, Tokyo (JP)

(74) Representative: Weser, Wolfgang, Dr. Dipl.-Phys. 
Weser & Kollegen, Patentanwälte, Radeckestrasse 43
81245 München
81245 München (DE)

   


(54) Substrate for ink-jet printing head, ink-jet printing head, ink-jet cartridge, ink-jet printing apparatus, and method for detecting ink in ink-jet printing head


(57) The present inventions allow the detection of ink in the printing head by significantly simplified their configurations and on which various printing systems can be widely applied. There are a heater (101) for supplying an energy to ejecting ink, a driver (102) for driving heater (101), and a detection electrode (118) capable of detecting a voltage variation between the heater (101) and the driver (102) to be occurred depending on the driving of the heater (101). Furthermore, an insulating film (410) that covers the surface of the detection electrode (118) prevents a chemical or physical change from the detection electrode (118). Furthermore, a reference element group or a reference unit that produces a signal as a reference of the detection signal avoids the influence of noise. Furthermore, an energy-generating element (101) and another signal source (101) improve the accuracy of ink-detection. A drive pulse which is insufficient to ejecting ink may be supplied to the heater (101) to improve the accuracy of ink-detection.






Search report